Doorcheck



Patented June 29, 1926.

UNITED STATES HENRY C. BOSSEBDET, OF DETROIT, MICHIGAN.

DOORGHECK.

Application filed November 25, 1922. Serial No. 603,143.

My invention relates to an improvement in door checks and pertains particularly to a pneumatic door check adapted to retard the movement of the door in closing or opening to prevent slamming of the door or bringing the same to a sudden stop. It is intended principally for use with a power operated door of the sliding type and of large size, such as a garage door as shown in the drawing, though it is obvious it might be attached to a vertically movable door or even a swinging door, and also to one which was intended for hand operation.

The object is to provide an improved simple and efiicient check which will effectively slow up the speed of the door a short distance before it arrives at its permitted limit of travel and cushion its halting as hereinafter more fully set forth and described. This door check is positive in operation irrespective of the direction of travel of the door, does not require a fluid under compression for its operation, and is always in position to check the movement of the door.

In the drawings:

Fig. 1 is a side elevation of a sliding door fitted with my improved door check.

Fig. 2 is a sectional view'through the door check.

It is highly desirable in the operation of large or rapidly moving doors that some means he provided to retard the travel of the door slowly before bringing the door to a complete stop, thereby cushioning the shock. This is particularly true in the case of heavy power operated doors. Further more, such cushioning means should be incnpensive, positive in operation and durable.

My improved door check might be attached to any type of door. I show the door check however in connection with a horizontally slidable door. The door is indicated as 5, mounted for travel on an overhead track 6 by means of wheels 7. he door, in the drawing, is broken away above the floor, the lower runway is not shown. Flexible connections leading to a suitable source of power, not shown, are indicated as 8.

The door check comprises an air cylinder fitted at each end with packing glands 10. Mounted within the cylinder is a pis ton, comprising a piston rod 11 which extends beyond each end of the cylinder. The

leather a flexible concave disk 12 mounted on the piston rod concave interiorly the cup leather and so disposed that the margin of the disk bears outwardly against the side flange of the cup leather to serve to hold the side wall. of the cup leather outwards against the cylinder wall as the air under compression forces the concave disk within the cup leather.

I have shown the cylinder as mounted on the door by means of straps 13, and positioned well up toward the top of the door so that the extended ends of the piston rod will not interfere with passage through the door opening. As here shown the piston rod travels through guides 1% carried by the door and projects beyond the edges of the door to be engaged by stationary stops carried by the door frame before the door has arrived at the limit of its permitted travel in either direction. When the end of the piston rod engages a stationary stop 15, during the movement of the door, the piston is forced through the air cylinder resisting the movement of the door and retarding its travel. It is evident that the air cylinder might be mounted on the door frame and the stops carried by the door and the result achieved would be the same.

The air cylinder is provided with an auxiliary air passageway or by-pass 16, which extends from one end of the cylinder to the other. When the piston leathers are moved toward one end of the cylinder, the air is exhausted from such end through the pass into the opposite end of the cylinder in the rear of the advancing piston. The by-pass is of considerably reduced diameter as compared with the diameter of the cylinder thus forcing of the air through this by-pass retards the movement of the door and cushions the shock of its halting. The air pressure in this cylinder, as I have shown it, is at atmospheric pressure, and the exhaust is merely back and forth from one end of the cylinder to the other.

lVha't I claim is: a

A check for a sliding door, comprising in combination with the door, a pneumatic cylinder carried by the door, a piston mounted within the cylinder having a piston rod extending through each end thereof and projectingbeyond each side of the door,

June 29,1926. 1,590,415

' C. W. BRAGG I FIN FOR mamas Filed June 9, 1922 

